1. Field of Invention
This invention relates to articles of manufacture and more specifically to a single-door, lockable rural mailbox.
2. Description of the Prior Art
The following paragraph describes the general problem that this invention addresses.
Rural mailboxes are commonly characterized by a single door in the front which is readily accessible to the homeowner and the mail carrier. This easy accessibility feature, while being a distinct advantage to mail carriers, does pose certain disadvantages for the homeowner. Unauthorized persons have the same accessibility as authorized persons. Thus, articles such as packages, checks, credit cards and mail, placed in the mailbox by the mail carrier are vulnerable to theft or vandalism. Since it is not functional for mail delivery purposes to employ a rural mailbox which requires unlocking by the mail carrier, persons on a rural or residential route with conventional mailboxes have suffered the inconvenience associated with an insecure mailbox.
Security mailboxes that maintain security automatically without immediate intervening action by the homeowner provide secure storage of incoming mail by either of two methods: The first method is by either having the received mail move to a position that can not be reached through the deposit opening because of distance, or access port size, or having a barrier between the receiving and storage compartments to prevent access to the storage compartment when the receiving door is open. Access to the mail is accomplished through a second door which is locked and unlocked by the homeowner. Outgoing mail is either placed on a shelf within the accessible enclosure or in a separate enclosure. This double-door method is exploited in several patents. The added door, divider or larger size of these inventions add cost and complexity above that for the present mailbox. The second method for providing security for delivered mail uses a single door with various devices and/or procedures to provide security.
U.S. Pat. No. 5,586,718 discloses a rural type mailbox having, attached to the enclosure a pivoted catch that is urged to null position by a spring. The catch is engaged by a keyed rotatable latch on the door. Variability of friction at the pivot reduces functional reliability and the device can be defeated by a thief using a probe inserted through a mail slot to deflect and disengage the catch.
U.S. Pat. No. 5,476,220 discloses a locking device for a rural type mailbox. Turning a key rotates a cam which compresses a spring that urges a catch. The catch is prevented from engaging the latch by a spring urged pin in the latch. When the door is opened, the catch is released and moves to the locked position. When the door is closed the spring urged pin in the latch is pushed back allowing the latch to engage the catch locking the door. The device requires several parts which increase cost. Also, for proper operation, sliding friction must remain low at several locations in the device. Expected variation of friction makes the device susceptible to jamming. This device can also be defeated by a thief using a probe inserted through a mail slot to deflect and disengage the catch.
U.S. Pat. No. 514,284 uses two hinged doors and a dividing wall which add to the cost. Mail must be inserted through a slot. The slot must be small enough that a thief cannot get his hand through it. This limits the size of the slot and therefore the dimensions of mail that can be inserted.
U.S. Pat. No. 3,802,619 describes a two-door mailbox containing a pivotable shelf. The shelf supports outgoing mail where it can be picked up by the mail carrier and limits access so a thief can not reach delivered mail through the mail insertion door. Delivered mail is retrieved by the homeowner through a second lockable door. The second door and shelf increase the complexity and manufacturing cost for this approach.